[Spark365]

Hi everyone!

I've encountered this issue recently on my e92 335i 2009 6mt. When I hit boost, the car throws a little "puff" of black/brown smoke, and seems to missfire a little bit when that happens. I feels like a "hiccup". Brown/black smoke makes me think that there's unburned fuel. Car has 200k km ( 124k miles), tuned with mhd stage 2, fbo. No error codes or check engine.

Thank you!

[iqraceworks]

Originally Posted by Spark365

Hi everyone!

I've encountered this issue recently on my e92 335i 2009 6mt. When I hit boost, the car throws a little "puff" of black/brown smoke, and seems to missfire a little bit when that happens. I feels like a "hiccup". Brown/black smoke makes me think that there's unburned fuel. Car has 200k km ( 124k miles), tuned with mhd stage 2, fbo. No error codes or check engine.

Thank you!

How old are your plugs and coils? What turbos are you running? If they are bigger than stock...you need a custom tune.

[Spark365]

Originally Posted by iqraceworks

How old are your plugs and coils? What turbos are you running? If they are bigger than stock...you need a custom tune.

Stock turbos. I don't know how old are the plugs/coils, I might start with that

[iqraceworks]

Originally Posted by Spark365

Stock turbos. I don't know how old are the plugs/coils, I might start with that

Yep.....it's ways a good idea to go through and do all of your maintenance first.....

[Spark365]

Originally Posted by iqraceworks

Yep.....it's ways a good idea to go through and do all of your maintenance first.....

Ok so I looked at the receipt the last owner gave me. Plugs and coils were replaced about 20k miles ago with eldor coils and oem plugs. Injector are index 12. Could plugs and coils still be the problem even after that low of miles on them? The car runs very fine except one random hiccup when boosting. I could not see any mention of carbon cleaning in the receipts, could carbon buildup be in cause here?

Thank you

[iqraceworks]

Originally Posted by Spark365

Ok so I looked at the receipt the last owner gave me. Plugs and coils were replaced about 20k miles ago with eldor coils and oem plugs. Injector are index 12. Could plugs and coils still be the problem even after that low of miles on them? The car runs very fine except one random hiccup when boosting. I could not see any mention of carbon cleaning in the receipts, could carbon buildup be in cause here?

Thank you

Plugs are cheap...I would start with a fresh set of 1 step colder NGK plugs gapped at .022"

[Spark365]

Originally Posted by iqraceworks

Plugs are cheap...I would start with a fresh set of 1 step colder NGK plugs gapped at .022"

All right, I'll order some! The car didn't do it for the past week, but I'll replace them anyway

[Jaronbwall]

Originally Posted by iqraceworks

Plugs are cheap...I would start with a fresh set of 1 step colder NGK plugs gapped at .022"

This, 100%. If you're unsure something has been done odds are it hasn't and will fail. It's a BMW.